Apparatus for spin flanging containers

ABSTRACT

A spin flanging machine for flanging the open end of container bodies, such as metal cans. The machine includes a drive shaft mounted for rotation on a supporting structure and a rotary turret is secured to the shaft and carries a series of flanging heads. Each head is provided with a plurality of flanging rollers which are adapted to engage the open end of the can. As the turret rotates, each head is rotated about its axis by the driving engagement of a pinion connected to the head shaft with a large fixed gear mounted on the supporting structure. The flanging heads are moved in a reciprocating manner towards and away from the can by a cam mechanism including a cam follower that is secured to the end of each head and engages a cam groove on the fixed supporting structure.

BACKGROUND OF THE INVENTION

In the manufacture of can bodies, such as beer or soft drink cans, theopen end of the can is initially necked down to a small diameter andthen flanged outwardly to provide a flanged neck capable of interlockingwith the can lid.

In high speed manufacturing operations, a spin flanging machine isnormally used to flange the necked-down ends of the cans. Theconventional spin flanging machine includes a turret which is mountedfor rotation on a central drive shaft and the turret carries a series offlanging heads. Each head includes a plurality of freely rotatableflanging rollers which are adapted to engage the open end of the can toflange the same as the head is moved into engagement with the can.

During the flanging operation, the cans are supported by a star-wheelconveyor secured to the turret, and as the turret and conveyor rotate,the rotating heads are programmed to move toward the open end of the canto flange the same and to retract from the can to enable the can to bedischarged from the conveyor.

Because the components of the spin flanging machine are required toprovide a number of specific movements, such as rotation of the turret,rotation of the flanging heads relative to the turret, and reciprocatingmovement of the flanging heads relative to the turret, a complicated andcostly drive mechanism has been used in the past to provide thesefunctions.

SUMMARY OF THE INVENTION

The invention relates to a spin flanging machine for flanging the openend of container bodies, such as metal cans, and which has a simplifieddrive mechanism, thereby reducing the overall cost of the machine, aswell as reducing maintenance and down-time.

According to the invention, a drive shaft is mounted for rotation withrespect to a fixed supporting structure, and a rotary turret is securedto the shaft and carries a series of flanging heads. Each flanging headis provided with a plurality of flanging rollers which are adapted toengage the open end of a container body or can to flange the same. Thecans are carried by a star-wheel conveyor that is secured to the turretand rotates with the turret.

Each of the flanging heads is rotated about its axis by a pinion whichis connected to the flanging head shaft and is engaged with a largefixed gear on the supporting structure. As the drive shaft and turretrotate, the pinions associated with the various flanging heads ride onthe large gear to thereby rotate the flanging heads about their axes.The flanging heads are programmed to move in a reciprocating path towardand away from the cans carried by the star-wheel conveyor by a cammechanism which includes a cam follower that is attached to eachflanging head shaft adapted to ride in a cam groove formed in thesupporting structure. As the turret rotates, each follower moves alongthe cam groove to thereby move the respective flanging head intoengagement with the can for the flanging operation and retract theflanging head from the can after the flanging operation has beencompleted.

As both the rotation of the flanging heads about their axes and theaxial movement of the flanging heads is initiated through fixed memberssecured to the supporting structure, the drive mechanism is considerablysimplified over that employed in conventional spin flanging machines.Simplification of the drive mechanism reduces the initial cost of themachine, as well as reducing maintenance and down-time.

With the drive system of the invention, as the speed of the main driveshaft is increased, the speed of rotation of the flanging head shafts iscorrespondingly increased, with the result that the flanging headsoperate on each can with the same number of revolutions for each workingcycle regardless of the speed of the main drive shaft. This enables thespeed of the machine to be varied through a substantial range withoutchanging the intensity of contact between the flanging rollers and thecan, thus insuring uniformity of quality regardless of any variation inthe speed of the machine.

With the spin flanger of the invention, no mechanism is required to holdthe can bottoms against the supporting plate of the conveyor during theflanging operation, as is normally required in conventional spinflanging machines.

The speed of stripping of the cans from the flanging heads at thecompletion of the working cycle can be increased by utilizing an airpressure release in which a blast of air is introduced through theflanging head into the interior of the can to aid in removing the canfrom the flanging head.

The spin flanger of the invention utilizes seven freely rotatableflanging rollers with each flanging head and this not only produces amore uniformly flanged can, but also enables the speed of rotation ofthe flanging heads to be reduced and prevents any tendency of the can torotate with the flanging head.

Other objects and advantages will appear in the course of the followingdescription.

DESCRIPTION OF THE DRAWINGS

The drawings illustrate the best mode presently contemplated of carryingout the invention.

In the drawings:

FIG. 1 is a side elevation of the spin flanging machine of the inventionwith parts broken away in section;

FIG. 2 is an enlarged fragmentary vertical section showing the centraldrive shaft and one of the flanging heads;

FIG. 3 is a section taken along line 3--3 of FIG. 2;

FIG. 4 is a section taken along line 4--4 of FIG. 2; and

FIG. 5 is an enlarged transverse section of one of the flanging headbodies.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The drawings illustrate a spin flanging machine for flanging the openend or neck of a container body such as a metal can. The spin flangingmachine includes a main drive shaft 1 having its ends journalled infixed supports 2 which extend upwardly from the base 3.

The shaft 1 is adapted to be rotated by any conventional drivemechanism, and as shown in FIG. 1, a sprocket 4 is connected to one endof the shaft and is adapted to be driven through a chain drive 5 by amotor, not shown.

A turret 6 having a central hub 7 is secured to the main drive shaft 1and includes a series of flanging head assemblies 8 which are mounted incircumferentially spaced relation on the outer surface of the hub 7. Asthe turret 6 is fixed to the shaft 1, rotation of the shaft will causerotation of the turret about the axis of shaft 1.

As best illustrated in FIG. 2, each of the flanging head assemblies 8includes an outer generally cylindrical housing 9 and a sleeve 10 islocated within each housing and the rear end of the sleeve projects asubstantial distance beyond the housing.

A flanging head shaft 11 is mounted for rotation within each sleeve 10by a pair of bearing assemblies 12 and 13, and a flanging head 13 issecured to the forward end of each shaft 11 by a central bolt 15.

As best shown in FIG. 5, each flanging head 14 includes a generallycylindrical body 16 and a plurality of flanging rollers 17 arejournalled for rotation on the body 14. Each of the flanging rollers 17includes an inner base ridge 18, a central cylindrical portion 19 and anouter tapered tip 20. In the flanging operation the tapered outer end 20serves as a guide to guide the roller into the can while the ridge 18engages the edge of the can 21 to deform the same outwardly and providethe flange.

Each of the flanging rollers 17 is provided with a shank 22 (See FIG. 5)which is journalled for rotation within an opening 23 in the body 16 bya bearing assembly 24. In addition, the inner end of each shank 22 isprovided with a shoulder which engages a thrust bearing 25 attached tothe plate 26 that is secured to the inner surface of the body 16.

As best illustrated in FIG. 2, the bolt 15 which connects the flanginghead 14 to the shaft 11 is provided with a central opening 27 whichcommunicates with an axial passage 28 formed in the shaft 11.

The passage 28 and opening 27 provide a conduit for conductingcompressed air or other gas to the interior of the can 21 to strip thecan from the flanging head 14, as will hereinafter be described.

Each of the flanging heads 14 is adapted to be rotated about its axis asthe turret 6 rotates about the axis of the main drive shaft 1. Toprovide the rotation for each head 14, a pinion 29 is secured to theouter end of the head shaft 11 by a key 30. Each of the pinions 29 isengaged with a fixed large gear 31. As best shown in FIG. 2, gear 31 issecured to a cam plate 32 by a series of bolts 33 and cam plate 32 isconnected to a supporting plate 34 by bolts 35. The supporting plate 34,in turn, is connected to the base 3. With this construction, as theturret rotates, each of the pinions 29 associated with the flanging headshafts 11 will engage the fixed large gear 31 to thereby rotate theshafts 11 about their axes.

A cap 36 is secured to the rear end of each sleeve 10 and the end of theshaft 11 is sealed with respect to the internal surfaces of the cap by asealing ring 37. A nut 38 is threaded on the end of the shaft 11 and islocated between the seal 37 and the pinion 29, as shown in FIG. 2.

To move each flanging head 14 toward and away from the respective can 21is programmed sequence, a cam mechanism is utilized which includes a camfollower 39 having a shank which is secured to a flange on cap 36 bymeans of a nut. A spacer 41, as illustrated in FIG. 3, is interposedbetween the cap flange and the follower.

Each of the followers 39 is adapted to ride within a cam groove 42formed in the cam plate 32 as the turret 6 rotates. The groove 42 isprovided with a contour such that each flanging head 14 is sequentiallymoved toward the can 21 to provide the flanging operation and is thenwithdrawn from the can after the flanging has been completed.

During the flanging operation, each can 21 is supported by a star-wheeltransferer 43 which is secured to the main drive shaft and rotates withthe turret 6. The star-wheel transferer 43 includes a pair of spacedplates 44 having a series of peripheral recesses or pockets 45 whichreceive the cans. The cans can be introduced into the pockets 42 of thestar-wheel transferer 43 either by a gravity feed system or by asuitable conveyor system. After the flanging operation, the cans 21 willfall by gravity from the pockets 45 of the star-wheel transferer.

In the flanging operation the bottoms of the can 21 bear against asupport plate 46 which is secured to the main driveshaft 1 and rotateswith the shaft. A wear ring 47 can be secured to the face of the supportplate and serve as a thrust surface for cans.

In order to facilitate removal or stripping of each can 21 from therespective flanging head 14 a pressurized gas can be introduced into theinterior of the can after the flanging operation. To provide thepressurized gas system, a sleeve 48 is secured around the shaft 1inwardly of the large gear 31 and cam plate 32 and the sleeve isprovided with axial passages 49 that are connected to a suitable sourceof pressurized gas. Each passage 49 is connected by a hose 50 to achamber 51 in one of the caps 36. Each chamber 51 communicates with thecentral passage 28 in shaft 11, which in turn is connected to theopening 27 in bolt 15, so that the gas can pass through the shaft 11 andbolt 15 to the interior of the can 21. The gas supply system is operatedin programmed sequence with the flanging operation so that the gas willbe supplied to the can as the flanging head is withdrawn from engagementwith the can. The blast of gas discharged into the can prevents the canfrom following the return movement of the flanging head and maintainsthe bottom of the can in engagement with the support plate 46.

The drive mechanism of the spin flanging machine of the invention issubstantially simplified over the drive mechanism normally used in spinflanging machines. Both the rotary motion for the flanging heads 14 andthe reciprocating motion for the heads is activated by stationarymembers, namely the stationary gear 31 and the stationary cam 32. As thedrive mechanism is simplified, the initial cost of the machine isreduced over that of conventional units and maintenance expense anddown-time is also decreased.

With the drive system of the invention an increase in speed of thecentral drive shaft 1 will also result in a corresponding increase inspeed of the flanging head shafts 11 and thus, each flanging head 14will engage the respective can for the same number of workingrevolutions regardless of the speed of the main drive shaft. Thisinsures a more uniformly flanged product regardless of the speed ofoperation of the machine.

With the unit of the invention no mechanism is required to hold the cans21 against the plate 46, for the cans are held merely by frictionalcontact. The gas supply system which blasts pressurized air into theinterior of the can after the flanging operation insures that the canswill not follow the flanging heads on the return stroke and will retainthe can bottoms in engagement with the support plate 46 after theflanging operation has been completed.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

We claim:
 1. A machine for spin flanging the open ends of containerscomprising, a supporting structure, a drive shaft mounted for rotationwith respect to the supporting structure, a turret secured to the driveshaft and disposed to rotate with the drive shaft, container holdingmeans carried by the turret for holding the containers during the spinflanging operation, a series of flanging heads carried by the turret,each flanging head being mounted for rotation about its axis and beingmounted for reciprocating axial movement with respect to the turret, afixed drive gear mounted on the supporting structure and disposedconcentrically of said drive shaft, each flanging head including aseries of circumferentially spaced freely rotatable flanging rollersdisposed to engage the open end of the container to flange the same, apinion connected to each flanging head and operably engaged with saidgear to rotate the flanging heads about their axes as the turretrotates, each pinion and the respective gear having substantiallydifferent axial lengths to enable the pinion to move axially withrespect to the gear and maintain a driving connection therebetween whenthe head is moved axially with respect to the turret, cam meansinterconnecting each flanging head and the supporting structure formoving the flanging heads axially with respect to the turret inprogrammed sequence to thereby move the heads toward and away from thecontainers being held by said container holding means, gas supply meansfor introducing a gas under pressure through each flanging head and intothe interior of the container to aid in stripping the container from theflanging head as the head is moved away from the container after theflanging operation, each flanging head includes a flanging head shaftjournalled with respect to the turret, said gas supply means includes achamber in said turret and communicating with a source of gas underpressure, and a passage located axially of each flanging head shaft andcommunicating with said chamber for conducting gas to the interior ofeach container. .Iadd.
 2. A machine for spin flanging the open ends ofcontainers comprising, a supporting structure, a drive shaft mounted forrotation with respect to the supporting structure, a turret secured tothe drive shaft and disposed to rotate with the drive shaft, containerholding means for holding the containers during the spin flangingoperation, a series of flanging heads carried by the turret, eachflanging head including a flanging head shaft journalled for rotationabout its axis and each flanging head including a series ofcircumferentially spaced freely rotatable flanging rollers disposed toengage the open end of a container to flange the same, means to rotatethe flanging heads about their axes as the turret rotates, means forproviding relative movement between the flanging heads and saidcontainer holding means to effect engagement of the heads and therespective containers being held by the container holding means and toeffect disengagement thereof, gas supply means including a chamber ineach head for introducing a gas under pressure through each flanginghead and into the interior of the container to aid in stripping thecontainer from the flanging head as the head is disengaged from thecontainer after the flanging operation. .Iaddend. .Iadd.
 3. A machinefor spin flanging the open ends of containers, comprising a supportingstructure, a drive shaft mounted for rotation with respect to thesupporting structure, a turret secured to the drive shaft and disposedto rotate with the drive shaft, container holding means for holding thecontainers during the spin flanging operation, a series of flangingheads mounted on the turret, each flanging head including an outertubular body and an internal shaft journalled for rotation about itsaxis with respect to the body, each shaft having an internal passageextending to the outer end thereof, each flanging head also including aseries of circumferentially spaced freely rotatable flanging rollersmounted on the outer end of the shaft and disposed to engage the openend of a container held by the container holding means to flange thesame, means to rotate the flanging head shafts about their axes as theturret rotates, means for providing relative movement between theflanging heads and the container holding means to effect engagement ofthe heads and the respective containers being held by the containerholding means and to effect disengagement thereof, each flanging headincluding a sealed chamber in said body communicating with the passagein said flanging head shaft, and a gas supply conduit for introducing agas under pressure into each chamber, said gas flowing through therespective passage to aid in stripping the container from the flanginghead as the head is disengaged from the container after the flangingoperation. .Iaddend.